1 # Copyright 2016 - The Android Open Source Project 2 # 3 # Licensed under the Apache License, Version 2.0 (the "License"); 4 # you may not use this file except in compliance with the License. 5 # You may obtain a copy of the License at 6 # 7 # http://www.apache.org/licenses/LICENSE-2.0 8 # 9 # Unless required by applicable law or agreed to in writing, software 10 # distributed under the License is distributed on an "AS IS" BASIS, 11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 # See the License for the specific language governing permissions and 13 # limitations under the License. 14 15 import shellescape 16 import signal 17 import time 18 19 from acts.controllers.utils_lib.ssh import connection 20 from acts.libs.proc import job 21 22 23 class ShellCommand(object): 24 """Wraps basic commands that tend to be tied very closely to a shell. 25 26 This class is a wrapper for running basic shell commands through 27 any object that has a run command. Basic shell functionality for managing 28 the system, programs, and files in wrapped within this class. 29 30 Note: At the moment this only works with the ssh runner. 31 """ 32 33 def __init__(self, runner, working_dir=None): 34 """Creates a new shell command invoker. 35 36 Args: 37 runner: The object that will run the shell commands. 38 working_dir: The directory that all commands should work in, 39 if none then the runners enviroment default is used. 40 """ 41 self._runner = runner 42 self._working_dir = working_dir 43 44 def run(self, command, timeout=3600): 45 """Runs a generic command through the runner. 46 47 Takes the command and prepares it to be run in the target shell using 48 this objects settings. 49 50 Args: 51 command: The command to run. 52 timeout: How long to wait for the command (in seconds). 53 54 Returns: 55 A CmdResult object containing the results of the shell command. 56 57 Raises: 58 job.Error: When the command executed but had an error. 59 """ 60 if self._working_dir: 61 command_str = 'cd %s; %s' % (self._working_dir, command) 62 else: 63 command_str = command 64 65 return self._runner.run(command_str, timeout=timeout) 66 67 def is_alive(self, identifier): 68 """Checks to see if a program is alive. 69 70 Checks to see if a program is alive on the shells enviroment. This can 71 be used to check on generic programs, or a specific program using 72 a pid. 73 74 Args: 75 identifier: string or int, Used to identify the program to check. 76 if given an int then it is assumed to be a pid. If 77 given a string then it will be used as a search key 78 to compare on the running processes. 79 Returns: 80 True if a process was found running, false otherwise. 81 """ 82 try: 83 if isinstance(identifier, str): 84 self.run('ps aux | grep -v grep | grep %s' % identifier) 85 elif isinstance(identifier, int): 86 self.signal(identifier, 0) 87 else: 88 raise ValueError('Bad type was given for identifier') 89 90 return True 91 except job.Error: 92 return False 93 94 def get_pids(self, identifier): 95 """Gets the pids of a program. 96 97 Searches for a program with a specific name and grabs the pids for all 98 programs that match. 99 100 Args: 101 identifier: A search term that identifies the program. 102 103 Returns: An array of all pids that matched the identifier, or None 104 if no pids were found. 105 """ 106 try: 107 result = self.run('ps aux | grep -v grep | grep %s' % identifier) 108 except job.Error: 109 raise StopIteration 110 111 lines = result.stdout.splitlines() 112 113 # The expected output of the above command is like so: 114 # bob 14349 0.0 0.0 34788 5552 pts/2 Ss Oct10 0:03 bash 115 # bob 52967 0.0 0.0 34972 5152 pts/4 Ss Oct10 0:00 bash 116 # Where the format is: 117 # USER PID ... 118 for line in lines: 119 pieces = line.split() 120 yield int(pieces[1]) 121 122 def search_file(self, search_string, file_name): 123 """Searches through a file for a string. 124 125 Args: 126 search_string: The string or pattern to look for. 127 file_name: The name of the file to search. 128 129 Returns: 130 True if the string or pattern was found, False otherwise. 131 """ 132 try: 133 self.run('grep %s %s' % (shellescape.quote(search_string), 134 file_name)) 135 return True 136 except job.Error: 137 return False 138 139 def read_file(self, file_name): 140 """Reads a file through the shell. 141 142 Args: 143 file_name: The name of the file to read. 144 145 Returns: 146 A string of the files contents. 147 """ 148 return self.run('cat %s' % file_name).stdout 149 150 def write_file(self, file_name, data): 151 """Writes a block of data to a file through the shell. 152 153 Args: 154 file_name: The name of the file to write to. 155 data: The string of data to write. 156 """ 157 return self.run('echo %s > %s' % (shellescape.quote(data), file_name)) 158 159 def append_file(self, file_name, data): 160 """Appends a block of data to a file through the shell. 161 162 Args: 163 file_name: The name of the file to write to. 164 data: The string of data to write. 165 """ 166 return self.run('echo %s >> %s' % (shellescape.quote(data), file_name)) 167 168 def touch_file(self, file_name): 169 """Creates a file through the shell. 170 171 Args: 172 file_name: The name of the file to create. 173 """ 174 self.write_file(file_name, '') 175 176 def delete_file(self, file_name): 177 """Deletes a file through the shell. 178 179 Args: 180 file_name: The name of the file to delete. 181 """ 182 try: 183 self.run('rm %s' % file_name) 184 except job.Error as e: 185 if 'No such file or directory' in e.result.stderr: 186 return 187 188 raise 189 190 def kill(self, identifier, timeout=10): 191 """Kills a program or group of programs through the shell. 192 193 Kills all programs that match an identifier through the shell. This 194 will send an increasing queue of kill signals to all programs 195 that match the identifier until either all are dead or the timeout 196 finishes. 197 198 Programs are guaranteed to be killed after running this command. 199 200 Args: 201 identifier: A string used to identify the program. 202 timeout: The time to wait for all programs to die. Each signal will 203 take an equal portion of this time. 204 """ 205 if isinstance(identifier, int): 206 pids = [identifier] 207 else: 208 pids = list(self.get_pids(identifier)) 209 210 signal_queue = [signal.SIGINT, signal.SIGTERM, signal.SIGKILL] 211 212 signal_duration = timeout / len(signal_queue) 213 for sig in signal_queue: 214 for pid in pids: 215 try: 216 self.signal(pid, sig) 217 except job.Error: 218 pass 219 220 start_time = time.time() 221 while pids and time.time() - start_time < signal_duration: 222 time.sleep(0.1) 223 pids = [pid for pid in pids if self.is_alive(pid)] 224 225 if not pids: 226 break 227 228 def signal(self, pid, sig): 229 """Sends a specific signal to a program. 230 231 Args: 232 pid: The process id of the program to kill. 233 sig: The signal to send. 234 235 Raises: 236 job.Error: Raised when the signal fail to reach 237 the specified program. 238 """ 239 self.run('kill -%d %d' % (sig, pid)) 240
